Wireless-telegraph receiving system



,Aug. 19 1930. c, s, IN ET-AL 1,773,355

WIRELESS TELEGRAPH RECEIVING SYSTEM Filed June 192s 8-Shets-Sheet 1 PM" GI 8mm asmmnm, w. WITT,

G.M.WR\GHT a 5.5. SMITH gtjtmm Qa M C. S. FRANKLIN ET AL WIRELESS TELEGRAPH RECEIVING SYSTEM Filed June 1, 1923 8 Sheets-Sheet 2 Aug. 19, 1930. c, s FRANKUN ET AL 1,773,355

WIRELESS TELEGRAPH RECEIVING SYSTEM Filed June 1923 8 Sheets-Sheet 3 33 UmbLaf MW Aug. 19, 1930. C. s FRANKLIN El AL 1,773,355

WIRELESS TELEGRAPH RECEIVING SYSTEM Filed June 1, 1925 8 Sheets-Sheet 4 (l/wanton Lumkuu, M. Wm, G-NLWPJGHT & 5.5. 5mm

Aug. 19, 1930. c, s, FRANKLIN ET AL 1,773,355

WIRELESS TELEGRAPH RECEIVING SYSTEM Filed June 1925 8 Sheets-meet 5 Mil INVENTOR v 4 assummm, wwm

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A ORNEY Aug. 19, 1930. c, s FRANKUN Er AL 1,773,355

WIRELES TELEGRAPH RECEIVING SYSTEM Filed June 1, 1925 8 Sheets-Sheet 6 INVENTOR C.S.FRANKUN, mwn'r BY G. M.WR\GM & 5.5. sm'm /6( /Qdm ATTORNEY Aug. 19, 1930. a. FRANKLifi ET AL 1,7

mastitis? TELEERAPH RECEIVING sYs'rmn Filed June 1, 1923 a Sheets-Sheet 7 A ORNEY 4v 6;. s. FRANKLIN ET AL V v v 1- 1 wmsLEss TELEGRAPH RECEIVING sYsT'sm ALLA 4 INVENTOR mm, 5.1mm,

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TTORNEY v Patented Aug. 19, 1930 PATENT OFFICE,

oHAELEs SAMUEL FRANKLIN AND BER-TEAM; JOH wrr'r, oE'LoNnoN, GEORGE MAU- RICE WRIGHT, OFCHESTERFIELD, AND SIDNEY BERTRAM SMITH, 0E CHELMSFORD,

ENGLAND, ASSIGNORS DELAWARE WIRELESS-TELEGRAPH ianonivrne SYSTEM Application filed June 1, 1923, Serial No. 642,758, and in Great Birtain January 15, 1923.

It is known that when a radiogoniometer is connected to two frame aerials as in the Bellini aerial, that direction of signals can be foundby rotating the moving coil which is connected to a suitable receiver.

According to ourinvention we connect to a common pair of frames two or more radiogoniometers. Thus two or more stations which are in different directions with respectto the receiving station may be received independently one common aerial irrespective of what their wave lengths may be. a This apparatus was disclosed and broadly claimed in a copending application of Charles S. Franklin and Bertram J. Witt, Serial No. 626,423, filedMarch 20, 1923.

comprises two sections, wound at right angles to one another, each section'forming part of section, which we will call the active section,

is coupled to a receiver circuit, while'that of the other section, which we will call the com pensating section, includes an adjustable resistance to compensate for the-'-reactive effect of the receiver. z

Alternatively we may providea pair of radiogoni'ometers for each receiver, the field coils of the first radiogoniometer being connected'to the'receiving antennae while the field coils of the other are connected to artificial serials possessing the same characteristics as the receiving antennae.

v The search coils are connected in series or parallel and are coupled to a rece ver through the usual tuning circuits; these search coils are mechanically coupled together and their windings are in opposition so that the coupling between the first search coil and the receiving antennae is anti-coupled via the artificial aerial.

Our invention is illustrated by the accompanying diagrams: 1

Fig. 1 is a simple arrangement conforming to the invention. 7 f p Fig. 2 is an arrangement similar to Fig.1 but including means for-reducing the reaction effects between the several circuits.

Fig. 3 is a modification.

Figs. Land-5 are. modifications disclosing We may employ'a special searchcoil which an arrangement for modifying the directional characteristics of theseveral receiver devlces. V 7

Figs. '6 and 7 are modifications combining the compensating means 0f Fig. 2 with the directional systems of Figs. land 5 respectively and, W 1 Figs. 8 and 9 are modifications combining the ant1=couplingmeans of Fig. 3 with the directional systems of'Figures 4 and 5 respectively.

,In Figure 1-, A, aerials (preferably aperiodic) of'a Bellini T0 RADIO CORPORATION'IOF AMERICA,.A CORPORATION, OF

A represent the loop Tosi system, B, B are the two receivers, C, 1

G being the field coils of'the tworadiogoniometers and D, D the search coils the circuits of which can'be tuned by means of condensers E, E ,"and include primaries F, F of transformers, by which the signalsare conveyed to receiving circuits G, G I

. With such an arrangement signals from two stations which lie in different directions maybe received in the two circuits G, G

The efficiency, however, of this simple system depends upon the tightness of-the couplings between the circuits and upon 1 the amount of reaction between the circuits. In order to -receiveon either circuit lIIdGPGDd'.

. ently with the greatest efficiency the coupling should be asitight as possible but inasmuch as the reaction between the circuits increases with the tightness of the coupling, the move'-' ment of one of the search. coils of one of the radiogoniometers will impair the efficiency of reception'of the other ra'diogoniometen Figures 2 and 3 show arrangements in which reaction 'is avoided so that both receivers may be arranged to act with the great: est possible efficiency without the movements of the search coil of-one radiogoniometer affectingthe. other." In other words, each receiver is independent of the other. Y

I In Figure 2 thesearch coil of circuit B comprises two sections D, d,'wound at right angles to one another; the active section D is connected as before'to a tuning'condenser I E andthe primary 'F bywhichthe circuit a is coupled 'to the receiving circuit G, whilethe compensating section all is connected in. a

tuned circuit comprising atuning condenser e, and inductance f and an adjustable resistance r to compensate for the reactive effect of the receiver. Similarly the search coil of receiver B is composed of two sections, the active section D and the compensating section (1 being connected to condenser e and inductance f and resistance T The two. tuned circuitsof each, search coil systemshould be made exactly equal in allrespects, namely, inductance, capacity resistance and mutual inductance to the aerial circuit. Also there should-be no-mutualinductance between thetwo sections of the search coil.

It is found that with such a system the reactive effect of one radiogoniometer upon the other will beconstantnomatter what may be the position of either search coil.

- In -Figure'. each receiver-comprises two radiogoniometers, C. D and C D being; connected; as before to the-loop aerials, A, A while 0 H and 0 H are similarly connected to artificial aerials a, a possessing the same characteristics as the loop aerials A, A The search coils:D:H- are connected in series in a circuit including as before tuning condensers and-v primaries of transformers by whichtheircircnits'are coupled-to the receiving circuits G D -H are connected in a similar circuit coupled: to: G The: coils D and H andalso-the coils D H are-mechanically connected and are arranged lin such a mannerthatthe couplings between the coils D D and the receiving aerials are anti coupled via the artificial aerials. As a resultfthereactiveefieot of either-of the circuits'D E H F and D E H F on'theiother isreduced to zero.v

Thus with.thearrangementishown in Fig ures 2; and 3it is possible to use tightlycoupled r-adiogoniometers and to receive efficiently on the tworeceivers 13,13 simultaneously'andalso it is; possible to rotate the polar curve ofeither without disturbing the. other. V

Figure 4 shows an arrangement by which a;heartshaped diagram may be obtained on eaohgreceiver. Thecentre points of the fixed coils Q C of the-two radiogoniometers are connected to earth'through inductan'ces L -L The circuit ofsearch coil D is tuned to one of the waves to be received and is coupled through the tuned;circuit K tothe inductance L and alsothrough an intermediate tuned circuit M. to. thereceiving circuit (3's, Similarly the circuit of the search coil D is tuned to a-second wave to be-received andEiS coupled through artuned-circuitzKi-i to the inductance L -wandv through; a tuned: inter-V mediate circuit M to. the receiving circuit G Each; of; the, receivers-is, therefore worked by a; circuit. whiohis associated; with, the: two. frames. A,.-A;- and also w-itha a plain aerial, namely 1 that which includes the: inductances- L3,; L 'llheywholei systemX-therefore gives :a:

heart-shaped diagram, provided the amplitude and phase of the potentials induced in the circuits of D, D for the different waves respectively are correct. The amplitudes can be easily adjusted bymeans of the couplings whilethe phases for each wave can be ad justed' by tuning the circuits K and K respectively, resistancesB, B being included in these circuits so that the adjustments may not-be too critical. This method of phase at: justment, that is, by varying the tune of an intermediate circuit, is a convenient means for obtaining the desired result, but any method of phase shiftingmay be employed instead.

If they couplings inthe radiogoniometers and those ofthe plain aerial circuit are small either of the radiogoniometers can be ad justed without seriously affecting the setting of the other.

A. critical value of the couplings which is dependent on the difference between the wave lengths being received may be employed. If this difference is a few per cent or more of either wave length no diminution in the strength of the signals will be noticed, but if the difference is verysmall or zero the couplings must be weakened below the op timnm in order to obtain complete independenceof'the two radiogoniometers-r Or the arrangement shown in Figures 2 or 3. may be-employed..

Figure 5 showsan arrangement which is similar to that of Figure 4 except that the radiogoniometers are removed to adistance from the frames and are connectedtothem by cables N N Here each frame is closed and-the frames-are coupledto the fixed coils of the radiogoniometers by transformers '1 T while the plain aerial is formed by connectlUU ing the middle point of the bottom limb of 7 each frameto earththrough a resistance 0 and'inductance P in parallel therewith, this inductance being coupled to the, middle pointsvof the-secondaries of the transformers T T.

The systemsrshown in Figures G and-7 are substantially similar to the. systems shown in Figures tz'and 5 respectively. Detailed description of these circuit arrangements and to and operate in the same manner: as Figures 4 and 5 respectively; In; these modifications the artificial aerials shown anddescribed in connection with Figure 3' are combined with the directive systems show-min. Figures 4 and 5. In this manner. c-ouplinmbetween the separate aerial systems-and associated coils are; antncouplrdvaa; the artlficiallaerials.

. search coil.

2. The combination of two loop antenna circuits, a pair of radio'goniometers each consisting of a pair of angula rly disposed :field coils and a movable search coil, means for connecting one field coil of each radiogoniometer to each antenna circuit and a separate signal receiving circuit connected to each search coil. v

3. The combination of two radio frequency directional antenna circuits, a plurality of radiogoniometerseach comprising a pair of field coils and a search coil having one field coil connected to one antenna circuit and the other field coil connected to the other antenna circuit, a signaling circuit connected to each search coil and means associated with each signaling circuit for compensating for reactive eilects. V

4:. The combination of two directional antenna circuits, a plurality of radiogoniometers each including a pair of field coils having one coil connected to each antenna circuit,

a search coil for eachradiogoniometer and a separate signaling circuit connected to each search coil and an artificial antenna connected r to each search coil.

5. The combination of two directional antenna circuits, a plurality of'radiogoniometers each including a pair of field coilsand a search coil, a separate signaling circuit connected to each search coil, a pair of artificial antennae and a plurality of radiogoniometers associated with said artificial antennae the search coil of each of said last named radiogoniometers being connected to one of said signaling circuits.

6. The combination of two directional antenna circuits, a plurality of radiogoniometers each including a pair of field coils and a search coil having one field coil connected to one antenna circuit and the other field coil connected to the other antenna circuit,

two artificial antenna circuits with characteristics substantially similar to those of said first named conducting circuits, a plurality of radiogoniometers each having a pair of field coils and a search coil and each having one field coil connected to' one artificial circuit and the other field coil connected to the other artificial circuit, a plurality of signah. I

I of field coils. and, a. search, coil, one field coil ing circuits each connected to asearcli coil of one of said first named radiogoniomet-ers and'to a search coil 01" said second named radiogoniometer and means for mechanicallyconnecting the search 0011s connected to the same signaling circult.

7. The combination of two directional antenna circuits, a plurality of radiogoniometers eachincluding a pair of field coils having one'coil connected to each antenna circuit, asea'rch coil for each radiogoniometer, a separate signaling circuit associated with each search coil, and means including tuning means associated with each of said search coils for compensating the reactive efiects caused thereby. Y 8.,The combination of two directional antenna circuits, a' plurality of radiogoniometers each including a pair of field coils having one coil connectedto each antenna circuit, asearch coilfor each radiogoniometer, a separate signaling circuit associated with each search coil, and coils associated with each .ot-saicl'searcl1 coils in such a manner as to prevent reaction between the signaling circuits. I .1

9;lhe combination of two directional antenna circuits, a plurality of radiogoniometers each including a pair of field coils having one .coil connected to each antenna circuit, a search coil for each radiogoniometer, a pair 01" circuits substantiallyelectrically equal to said antenna circuits, a plurality of radio goniometers associated with said last named circuitsand a plurality of receiving circuits each associated with. a search coil of one of said first named. radiogoniometers and with a search-coil of one of said last named radiogoniometer.- I

' 10. The combination of two loop aerials, a plurality of conducting circuits associated with said:aerials,a plurality of ra'diogoniometers each having a field coil associatedrwith each of said conductingcircuits,'and a receiving circuit associated with the search coil'of each of said radiogoniometers.

11..The'co1nb1nat1on of two loop a'erials, a-

plurality of conducting circuits, a plurality of each of said circuits, a radio frequencysignah ingcircuit associated withf each of .said

antennm circuits, andameans including a ro-.

tatable search coil for each signaling circuit forcouplingsaid signalingci-rcuit to all of said antennae circuits toipermit independent signaling in each signaling circuit-. I

13, The combination of two radiofrequen cy directional conducting c1rcu1ts,a pl-urality of 'rad ogonlometers each comprising a pair of each of said: radiogoniometers being coupled to one conducting c1rcu'1t and the other field coil beingcoupled to -the other conducteach signaling circuit for compensating for reactive effects, said means comprising a coil in angular relation to the search coil.

14. The combination of a plurality of directional aerial circuits, a plurality of radiogoniometers each including a plurality of field coils one of each of which is coupled to each of said aerial circuits, a search coil for each radiogonionieter and a signaling circuit connected to each search coil, a coil at right angles to each search coil and a separate circuit containing tuning elements connected to each of said last named coils.

-15. The combination of two directional aerial circuits, a plurality of radiogoniometers each connected to each directional aerial circuit, a receiver connected with the search coil of each of said radiogoniometers and means for preventing interference between signals in said receivers including including inductances angularly disposed with respect to said search coils.

16. Apparatus as claimed in claim 15 in which each of said inductances are included in a tuned circuit.

17. The combination of two directional antenna circuits, a non-directional antenna circuit associated with said circuits, a plurality of radiogoniometers each having a pair of field coils and asearch coil, one of said field coils being connected to one of said directional circuits and the other being connected to the other directional circuit, and a plurality of signaling circuits each connected to the search coil of one of said radiogoniometers and to said non-directional antenna circuit. 7 I

18. The combination of two directional receiving antennae, a non-directional receiving antenna, a plurality of radio receiving circuits, means for connecting the latter to said non-directional antenna and a radiogoniometer for connecting each receiving circuit to each of said directional antenna whereby independent signals from'diiferent directions may be received in each receiving circuit simultaneously. b

19. The combination of a plurality of directional aerial circuits, a plurality of radiogoniometers each of which are connected to each of said aerial circuits, a separate receiver connected to each of said radiogoniometers,

and a vertical aerial associated with said radiogoniometers, and said receivers.

'20. The combination of a plurality of frame aerial circuits, a plurality of radiogoniometers each associated thru field coils with all of said frame aerials, a separate research coil coupled with the field coils of each of said radiogoniometers, a separate receiver connected to each search coil, means for preventing interference between signaling currents in said receivers including a tuned inductace angularly disposed with reference to each of said search coils, and a vertical aerial coupled to each of said search coils.

CHARLES SAMUEL FRANKLIN. BERTRAM JOHN WITT. GEORGE MAURICE WVRIGHT. SIDNEY BERTRAM SMITH.

ceiver-associated with each of'sa'idradiogoniometers, andmeans for impressing a vertical aerial eifecton each of said receivers.

21. The combination of a pair of angularly disposed frame aerials, a plurality of radiogoniometers each having a field coil connected with each of said frame aerials, a

CERTIFICATE OF CORRECTION.

Patent No. 1,773,355. Granted August 19, 1930, to

CHARLES SAMUEL FRANKLIN ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, line 54, claim 6, for "conducting" read antenna; line 62, before "said" insert one of, and line 63, for "radiogoniometer" read radiogoniometers; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 9th day of December, A. D. 1930.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

